why does fine Particles penetrate the geometry?

Ahmed Rami
Ahmed Rami Altair Community Member
edited March 2022 in Community Q&A

My name is Ahmed Rami, I am a student at Universiti Teknologi PETRONAS. while I was using Altair EDEM to do some simulations I faced a problem I couldn't solve by myself. For some reason while doing the simulation I noticed that some of the particles are penetrating the geometry and I have no idea on why is that happening. 

I tried increasing the shear modulus and reducing the time step as someone suggested and it did stop the particles with 0.005 Meters physical radius from penetrating the geometry but when dealing with fine sand which has a physical radius of 0.0002 Meters the particles just penetrate the geometry as if there was no geometry at all.

Note: Im using

  • steel as a geometry material with a solid density of (8050 kg/m^3)
  • sand as a particle material with a solid density of (2600 kg/m^3)

I also included some pictures of the properties of both sand and steel.

Tagged:

Best Answer

  • Stephen Cole
    Stephen Cole
    Altair Employee
    edited March 2022 Answer ✓

    Hi Ahmed,

     

    What time-step are you using?  We typically recommend ~20% of the Raleigh time-step value.

     

    Also can you check if the Particle Properties are calculated correctly in the Creator > Bulk Material > Particle Name > Properties tab.  If the mass, volume and inertia are not correct then it can cause strange behaviour.  Just to note this should be done at t=0 s before any particles are created as any changes to the properties only affect newly created particles not any existing ones.

     

    Which Physics model are you using for Particle-Particle and Particle-Geometry interactions? Any other additional physics used?

     

    Regards

    Stephen

Answers

  • Stephen Cole
    Stephen Cole
    Altair Employee
    edited March 2022 Answer ✓

    Hi Ahmed,

     

    What time-step are you using?  We typically recommend ~20% of the Raleigh time-step value.

     

    Also can you check if the Particle Properties are calculated correctly in the Creator > Bulk Material > Particle Name > Properties tab.  If the mass, volume and inertia are not correct then it can cause strange behaviour.  Just to note this should be done at t=0 s before any particles are created as any changes to the properties only affect newly created particles not any existing ones.

     

    Which Physics model are you using for Particle-Particle and Particle-Geometry interactions? Any other additional physics used?

     

    Regards

    Stephen

  • Ahmed Rami
    Ahmed Rami Altair Community Member
    edited March 2022
    Stephen Cole_21117 said:

    Hi Ahmed,

     

    What time-step are you using?  We typically recommend ~20% of the Raleigh time-step value.

     

    Also can you check if the Particle Properties are calculated correctly in the Creator > Bulk Material > Particle Name > Properties tab.  If the mass, volume and inertia are not correct then it can cause strange behaviour.  Just to note this should be done at t=0 s before any particles are created as any changes to the properties only affect newly created particles not any existing ones.

     

    Which Physics model are you using for Particle-Particle and Particle-Geometry interactions? Any other additional physics used?

     

    Regards

    Stephen

    I forgot to calculate the properties after changing the  physical radius, now that I did that everything is working perfectly. THANK YOU.

Categories